1. Field of the Invention
The invention relates to a method of and apparatus for compacting powder in which there is a dolly against which a cup is intended to bear, means for containing a sufficient volume of non-compacted powder above the cup, and a hydraulic ram capable of displacing a punch intended to effect the compacting of the powder in the cup; this punch effects an approach stroke during which the powder is not subjected to any compression, then a contact stage corresponding to the start of the compression of the powder, then a stroke termed a "debubbling" stroke, during which the air or other gas contained in the powder is ejected and at the end of which stroke the displacement of the punch is practically stopped but the pressure is maintained in the ram to ensure the compacting for an adequate period.
The invention concerns more particularly, but not exclusively, the compacting of cosmetic powder, because it is in this case that its application seems to be most advantageous.
2. Description of the Related Art
The compacting machines known to date, in particular for cosmetic powders, are not completely satisfactory, because the percentage of rejects during manufacture is relatively high. In particular, these rejects are the result of the formation of lumps in the cake of compacted powder, or the breakage of this cake or other defects rendering the product unsuitable for commercial use.